With regard to _narrow passes_, if you can occupy them first,
Capt. Calthrop says: “Defiles, make haste to occupy.” But this is
a conditional clause, answering to 若敵先居之 in the next paragraph.
let them be strongly garrisoned and await the advent of the enemy.
Because then, as Tu Yu observes, 皆制在我然後出奇以制敵 “the
initiative will lie with us, and by making sudden and unexpected
attacks we shall have the enemy at our mercy.” The commentators
make a great pother about the precise meaning of 盈, which to the
foreign reader seems to present no difficulty whatever.